Method for brewing coffee



Aug. 9, 1960' T R. SAINT METHOD FOR BREWING COFFEE 4 She'ets-Sheet 1Filed Dec. 23, 1957 INVENTOR. 7844p Jhnvr A rrap/vsr Aug. 9, 1960 T R.SAINT' 2,948,618

METHOD FOR BREWING COFFEE Filed D60. 23, 1957 4 Sheets-Sheet 2 INVENTOR.5 I 71844.1 SAM/r 1 Arrows) Aug. 9, 1960 Filed Dec. 23, 1957 T SAINTMETHOD FOR BREWING COFFEE 4 Sheets-Sheet 4 INVENTOR.

Patented Aug. 9, 1960 METHOD non BREWING COFFEE T "Ralph Sa'int, Bogota,'N.J., assigno'r to Jabez Burns & gonlsx, Inc, New York, N.Y., a"corporation of New 'or Filed Dec. 23, 1957, Se'r. No. 704,630

3"Ciaims. '(Cl. 99-''71) This invention relates to a method for brewingcoflee and tea, particularly coffee, in small quantities by drainingwater at a temperature just below 'b'oilin'g through the coffee groundsand separating the coifee grounds from the brew to form a clear brew ofthe desirable coflee tasting compounds.

"Coffee makers, particularly small sized coffee makers for domestic use,should meet certain requirements. These requirements may generally bedivided into two groups, one relating to the brewing of good conee andthe other relating to the components of the co'flfee maker. In brewingcofiee, an extraction of the desirable coffee tasting compounds shouldbe obtained within a period of less than ten minutes with -a completeseparation of the coffee grounds-and the accompanying sediment from thebrew resulting in a clear coffee brew. The coffee making apparatusshould be so constructed as to be free from contamination due 'torepeated use, producing equally good results from each brewingoperation. In addition, the apparatus should be simple in structure andinexpensive to manufacture. The attention required by the apparatusduring the brewing process should be 'at a minimum and the processshould complete itself without further attention than that of setting upthe apparatus and addingthe water and ground coffee.

'The main object of this invention is to provide a brewing process andapparatus which fully meets the above requirements and providessubstantially the same percentage of extraction from the cofiee granuleseach time coflee is brewed.

Other objects of the invention will become apparent from the followingdescription taken in connection "with the drawings, in which:

Fig. l is a sectional view of the coffee maker and 'the receptacle forreceiving the coffee brew.

Fig. 2 is a detailed fragmentary view of the bottom o'ffth'e waterreservoir.

Fig. 3 'is a detailed sectional view of one of the openmgs.

Fig. 4 is a detailed sectional view of the apex opening of 'the conicalmember holding the coflee.

Figs. 5, 6 and 7 are fragmentary sectional views illustrating the coffeebrewing process.

Fig. 8 illustrates the 'coflee maker with an automatic heating andsupplying of the water to the reservoir.

,Fig. '9 illustrates a stand for supporting the liquid reservoir holdingmember.

In Figs. 1 to 4 an embodiment of a coffee maker is shown 'in accordancewith the invention. In this embodiment the coiiee maker is supported bya receptacle '10,into which the final coffee brew is delivered. Thecoffee maker comprises a conically shaped coffee holding inember 11supported by an outer casing 12 which fits in the neck 13 of thereceptacle 10. A liquid reservoir holding member 14 sets on top of thelower unit and has a bottom 15 to form a chamber 17 above the bottom forholding the water for delivery to the conical unit. The wall 18 extendsbelow the bottom 15 to form the space 16 below the bottom of thereservoir member 14 and the top of the conical member 11. The wall 18 ofthe reservoir member and the casing 12 are preferably cylindrical inshape. The conical member 11 has smooth, solid walls extending from theapex to the flange 19 em gaging and secured to the flange 24 of thecasing 12. The apex has a cylindrical opening 21 axially aligned withthe axis of the conical member, as shown in detail in 'Fig. 4. The apexopening has a small diameter to restrict the flow of brew from the endof the conical member. At the upper end of the conical member a row ofoverflow openings 22 is provided extending circumferentially around theconical member. The overflow openings prevent the mixture of water andgrounds from rising above the upper edge of the filter paper 23 fittingin the conical member, as shown in Figs. 5 to 7. In the embodiment shownin Fig. 1, sixteen openings are provided. However, a number of rows anddifierent sized openings may be'used instead of a single row.

The casing 12 has a cylindrical portion 24, a conical portion 25 and anend cylindrical portion 26 for fitting in the receptacle 10. The casing12 is spaced from the conical member to form an insulating chamber 27 tomaintain the coffee brew at the proper temperature within the conicalmember. A vent opening 28 is provided in the cylindrical wall 24 forexhausting the vapors and steam from the receptacle 1% and retaining thepressure Within the casing and receptacle at atmospheric pressure sothat the brew will readily drain from the conical member.

The wall 18 of the reservoir member has a slightly smaller diameter thanthe cylindrical member 24 and the conical member and extends radiallywithin the upper edge of the conical member so that condensation ofsteam from the brew in the conical member drips back into the chamberformed by the conical member. A circumferential flange 29 is formedaround the bottom edge of the 'wall 18 for engaging the flange of thecasing 12 and the conical member 11 to support and hold the reservoirmember on the casing 12. The upper end of the reservoir member is openand a cover 31 with a knob 32 may be provided for snugly fitting andclosing the top of the chamber 17. A vent opening 33 is provided in thecover, and a vent opening 34 is provided in the wall 18 below the bottom15 to vent the steam from the apparatus and maintain the chamber 16 atatmospheric pressure.

Generally, the process comprises fitting the casing 12 with the conicalunit 11 in the receptacle 10 and placing a conically shaped filter 23into the conical member to rest against the inner surface of the walland extend from the apex opening to a given distance above the overflowopenings 22. The desired amount of ground coffee is then measured intothe filter paper and the unit 14 is set on top. The boiling water isthen added in a measured quantity to the chamber 17. Under the pressureof the head of water in the chamber 17 the water is forced through theopenings 35 and 36 in continuous streams which fill the chamber of theconical member with a mixture of water and coffee to a level above theoverflow openings 22. The cofiee brew drains through the opening 21 andthe overflow openings 22 and collects in the receptacle It The brew isseparated from the cofiee grounds and sediment by the filter paper 23.As the water finally drains from the chamber 17, the level of themixture 'of coflee grounds and water drops and the final brew drainsthrough the apex opening 21. Circumferentially spaced indentations 37are provided in the conical member at a distance above the apex 21 tospace the filter paper away from the conical member in order to providechannels for draining the brew around the spent grounds collected at thebottom of the filter paper. The indenta- Y tions are preferably formedin two rows of four indentations each with the indentations of the tworows staggered. When the brew has finally drained from the conicalmember, the reservoir member 14 may be removed and the filter papercontaining the spent coffee grounds lifted out and disposed of.

The conical member is preferably made of stainless steel or any othersuitable non-contaminating material and after use it need only be rinsedwith clear, warm water to remove any of the brew adhering to itssurface. As only clear water has come into contact with the reservoirmember, this member need only be dried. The

casing 12 and conical member may be then removed from the receptacle 10and the coffee is ready to serve. The filtering means is preferably afilter paper. However, other suitable means which separate the brew fromthe grounds and sediment may be used.

The water in the chamber 17, while draining into the conical member, isat approximately 205 F. The draining action and the contact of the waterwith the ground coffee drops the temperature of the water in the chamberof the conical member to between 185 and 200 F. The temperatures in thechamber 17 and in the conical member remain substantially constantthroughout the brewing process so that the coffee grounds arecontinuously bathed in a brew of between 185 and 200 P. which extractsall of the desirable coffee solubles and leaves the bitter tasting,undesirable coffee solubles in the granules.

Considering the brewing process in greater detail in connection withFigs. to 7, the openings 35 are clustered in the center of the bottom 15over the apex of the conical member. The upper and lower edges of eachof the openings are beveled to produce the desired type of flow andaction required to secure the proper extraction from the coffee grounds.A cross sectional view of one of these openings is shown in Fig. 3. Thecenter opening 35 is slightly smaller than the other openings 36 and theupper and lower edges are beveled to secure the proper flowing action.The pressure produced by the head of water in the chamber 17 causes thestreams 39 and 40 to issue from the openings 35 and 36, respectively, ata rapid and forceful rate to penetrate and saturate the grounds in theconical chamber. The flow is of such a rapid rate that it penetratesthrough the center of the grounds and a trickling of coffee brew issuesfrom the apex opening 21. The rapid flow of water fills the conicalmember, soaking some of the coffee grounds at the center and lifting theground coffee around the stream. The carbon dioxide and air adhering tothe surface of, and in the spaces between the coffee grounds causes thegrounds to float on the surface of the water and rise with it, asindicated in Fig. 6. The water level rises above the openings 22 and anequilibrium is reached between the draining of the water from the apexopening 21 and the overflow orifices 22 and the delivery of the waterfrom the orifices 35 and 36. As the ground coffee is rising with thelevel of the water, a depositing of grains and an extraction of the brewis occurring. The agitation of the water produces a washing of thegranules to remove the coffee oils.

The force of the centrally clustered streams 39 and 40 causes thestreams to penetrate the water 41 in the conical chamber, carrying thegranules coming in contact therewith down into the bottom of the conicalmember. force of the streams churns the water and causes the water tocirculate and rise adjacent to the sides of the conical member and sweepalong the bottom of the floating granules. The granules are swept by thewashing action and are freed of the carbon dioxide on their surfaces.They then sink slowly through the water 42 which is being turned into acoffee brew by the extraction of the coffee oils from the granules dueto the washing action and the dropping movement of the granules throughthe water 42. As indicated by the arrows in Fig. 6, the motion of thewater in the center between the central The ' downward stream and theside of the conical member is upward. This motion is counter to thedownward movement of the granules from the floating layer. This movementof the grounds and the water in opposite directions has the furthereffect of sweeping the granules free of the carbon dioxide and removingthe desirable coffee tasting compounds. A further washing action isproduced by the movement of the brew draining through the overflowopenings. This movement is along the peripheral edge area of thefloating granules which extends circumferentially around the conicalmember.

The head of water in the chamber 17 diminishes with a correspondingdiminution of the force of the streams, and by the time the water fromthe chamber 17 is expended, nearly all of the coffee grounds have beenstripped from the floating layer and those remaining on the surface ofthe water are suspended in carbon dioxide bubbles forming a foam acrossthe surface of the water. These granules are separated from the foam bya subsequent and different action of the water draining from the chamber17. The remaining water, due to the size of the openings 35 and 36 andthe loss of head in the chamber, instead of issuing as a stream from thebottom plate 15, forms droplets which drip at a continuous rate from theopenings in the plate 15 and impinge on the center area of the surfaceof the water 42. This central impingement on the water sets up arhythmic wave motion propagating from the center area outwardly to theedges of the water along the filter. This wave motion provides aconstant agitation of the surface of the water, and the wave agitationof the remaining granules breaks up the foam of bubbles and granules andcauses the coffee granules to drop down through the water 42. Thedroplet action is facilitated by the concave shape of the bottom 15 andthe shape of the openings therein. The bottom '15 is bowed so that thelowest part of the bottom is the center portion containing the openings35 and-36. The remainder of the water collects at the center portion anddrips through the openings. The upper and under edges of the openingsare beveled so that the water will readily pass through the openingswithout pressure and at the very end the droplets may adhere to thebottom and collect at the opening in the center. The water then dropsoff the bottom. The size of the openings and the distance of the levelof the water from the bottom 15 is important. The level of the watershould not be less than a distance A from the bottom 15 in order toprovide suflicient energy to the drip to form waves on the surface ofthe water. This distance should be sufiicient to form a droplet whichgains suflicient speed to strike the surface of the brew with force.

The ground coffee is subjected to a washing and agitating action toextract the coffee solubles from the coffee grounds. The conical chamberis of a size to receive the required amount of coffee and to submergethe coffee completely. The rate of the discharge of the water from theapex opening is slower than that of water from the chamber 17. The waterin the conical member builds up, raising the level of the water and thefloating granules. The water in the conical chamber maintains its levelby the feeding of water into the chamber faster than it drains from theconical member. The level is maintained to present a larger surface forthe action of the droplets, so that a full wave effect is produced. Thelevel drops slowly so that the dripping water from the chamber 17 hastime to separate the remaining floating granules. The streams come fromthe bottom until the granules drop to the bottom, except for thegranules suspended in the foam. The droplet action then commences toproduce the wave action which shakes the remaining granules free.

In the drawing, the openings in the bottom 15 are clustered in thecenter of the plate. The spent grains 30 collect at the bottom and onthe sides of the filter and by the time the last of the granules havehad the coflfee 5's extracted therefrom, the water from the chamber isexpended, or the level of the water which is now a coffee brew hasdrained off through the openings 22 and dropped below them, so that theremaining water drains'through the filter paper and the apex opening 21.The final draining of the coffee brew through the apex opening 21 occursat such a rate as to complete the draining of the water or coffee brewWithin a period of generally ten minutes.

The coffee maker may be adapted to various capacities. In a coffee makerhaving a maximum capacity of six cups the conical member has a depth-of4% inches and a diameter of 5 inches across the upper open end. Thechamber 17 has a diameter of 4% inches and a height f-3'As inches andcan holdfrom two to six cups of water. The center of the bottom plate isapproximately inches above the apex and the overflow openingsapproximately 3 /8 inches from the apex. The apex opening 21 has adiameter of .0595 inch and the sixteen overflow openings 22 each have adiameter of .1285 inch. The openings 35 and 36 in the bottom 15 havediameters of .042 and .035 inch, respectively, and are preferablycircumferentially arranged within a radius of one-half an inch. Withthese openings the brew will rise to within two to two and one-halfinches from the bottom plate at full capacity. The percentages ofextraction of runs using from two to six cups of Water are set forth inthe following Table I.

Table I Percent Extrac- Percent Extrac- N umber of Cups tion of Totaltion of Coffee Weight of Coffee Tasting Solubles For an eight cup coffeemaker the dimensions and hole sizes would be changed to secure the typeof operation described above. A table of the percentages of extractionusing from three to eight cups of water is set forth in the followingTable II.

It may be seen from these tabulations that nearly a complete extractionof the desirable coffee compounds may be obtained over a range ofamounts of water.

The requisites have been fulfilled. A complete extraction of thedesirable coffee compounds has been secured without removing the lessdesirable tasting compounds. The coffee brew is separated from thegrounds and sediment so that the brew has a clear, pleasant color and ataste uncontaminated by sediment.

The coffee maker is inexpensive to manufacture. The reservoir member andthe lower member are easily manufactured by inexpensive and well-knownprocesses and do not require any intricate shapes or forms. There are nosurfaces or corners which become contaminated with spent coffee. Theonly member requiring cleaning after each use is the conical member,which may be freed of any contamination by rinsing with water. The useof detergents or the scrubbing of the various parts is not required.Thus, after each use a minimum of attention is required to restore theunit to a condition suitable for subsequent coffee brewing. Therefore,there is no acesteem 6 cumulation of coifee deposits through repeate'duse without adequate sub equent cleaning.

The manipulative steps are at a minimum and noattention to the brewingis required once the process is initiated. Theopenings in the "bottomplate regulate the flow of water into the conical member and produce "astirring action which brings each ground into contact with the water fora sufficient period 'of timetol p'ermit a complete extraction.

Another advantage arising from the versatility of the apparatus is thatany type of coffee maybe used. The coffee may be of the regular grind,drip type or silex type of grind. Thus, the coffee maker can use any ofthe "grinds presently-available. I

The process may be made fully automatic by providing'a stand with anautomatic wa'terheaterwhich raises the water to the boiling point andthen delivers it to the chamber -17. This is diagrammatically indicatedin Fig. 8 in which the base 50 has a chamber 51-for containing water upto an amount of eight cups. A heating element 524s located in the basewhich may be made of metal. The pipe 53 ismounted in the base andconnected to the chamber 51. The pipe has a spout 54 to direct the waterinto the chamber 17 when it reaches the boiling point and is forced outof the chamber by the steam. The receptacle 10 sets on the casing, butis at a temperature below 200 Frand preferably atapproximately to F. tokeep the coffee hot.

In Fig. 9 another improvement is illustrated for ease in handling thecoffee maker. -A stand '60 is provided with a base '61 and-anupright-support 62. The-support 62 has an arm 63 with a clamp 64. Theclamp holds the container 14 in position above the conical member sothat the conical member and the glass receptacle can be moved out fromunder the container 14. Thus, the container 14 may remain in place whilethe conical member is removed for filling with coffee or removing thespent granules and washed. The clamp is held closed by a bolt 65 and awing nut 66, or other suitable fastening means. A hot plate 67 may beprovided to maintain the brew hot. If the hot plate is not used, thefastening means may be loosened and the container lowered and positionedon the conical member. Thus, the proper relation may be maintainedbetween the orifices in the bottom and the level of the brew.

Thus, it may be seen that with a minimum of effort a fine tasting coffeebrew may be repeatedly and economi cally made. However, the inventionmay also be used to brew tea or other similar products.

The apparatus described in this invention may be modified and changedwithout departing from the invention as set forth in the appendedclaims.

I claim:

1. A process for brewing coffee comprising forming ground coffee in amass, subjecting the coffee to streams of water at 185 F. to 200 F.impinging on the center portion of the mass and filling the mass withwater forming a body of hot water with a layer of ground coffee floatingon the surface of the water, subjecting the layer of ground coffee tostreams of hot water impinging on the center of the body of hot waterand carrying granules of coffee downward and then circulating the waterupward to sweep the water along the bottom of the layer and removecoffee granules therefrom until a thin layer of ground coffee remains onthe surface in bubbles of escaped gases, dropping the granules down wardthrough the water to extract the coffee therefrom while separating thecoffee brew from the coffee granules, subjecting the remaining thinlayer of coffee to a dripping action over a period of time to strip theremaining coffee granules from the bubbles on the surface and finallyseparating the coffee brew from the cofiee grounds to form a clearcoffee brew.

2. A process for brewing coffee comprising forming ground coffee in amass, subjecting the coifee to streams of water at 185 F. to 200 F.impinging on the mass and filling the mass with water forming a body ofhot water with a layer of ground coffee floating on the surface of thewater, subjecting the layer of ground coffee to a steady flow of hotwater impinging on a small por tion of the surface of the water anddriving through the layer of ground cofiee with the body of hot watercarrying granules of coffee downward and then circulating upward tosweep the water along the bottom of the layer and remove coffee granulestherefrom until a thin layer of ground coffee remains on the surface inbubbles of escaped gases, dropping the granules downward through thewater to extract the cofiee therefrom while separating the cotfee brewfrom the cofiee granules, subjecting the remaining thin layer of coffeeto a dripping action over a period of time to strip the remaining coffeegranules from the bubbles on the surface and finally separating thecoffee brew from the coffee grounds to from a clear coifee brew.

3. A process for brewing coffee comprising forming ground coffee in amass on a filtering medium, subjecting the coffee to a steady flow ofwater at 185 F. to 200 F. impinging on the mass and filling the masswith water forming a body of hot water with a layer of ground coffeefloating on the surface of the water, withdrawing the coffee brewthrough the filtering medium at a substantially steady flow to maintainthe free surface of the body of water at a substantially constant level,subjecting the layer of ground coffee to a steady flow of hot waterimpinging on a small portion of the surface of the water and drivingthrough the layer of ground coffee with the body of hot water andcarrying granules of cofiee downward and then circulating upward tosweep the Water along the bottom of the layer and remove cofiee granulestherefrom, dropping the granules downward through the water to extractthe coffee therefrom while separating the coffee brew from the coffeegranules, forming a thin layer of the remaining coffee grounds suspendedin bubbles of escaped gases on the surface of the water, discontinuingthe steady flow of water and subjecting the remaining thin layer ofcoffee to a dripping action over a period of time to strip the remainingcoffee granules from the bubbles on the surface and finally separatingthe coffee brew from the coffee grounds by drawing the coffee brewthrough the filtering medium to form a clear coffee brew.

References Cited in the file of this patent UNITED STATES PATENTS1,549,840 Lemmoine Aug. 18, 1925 1,648,699 Shroyer Nov. 8, 19271,971,490 Keith Aug. 28, 1934 2,107,236 Cory Feb. 1, 1938 2,273,422Schroeder Feb. 17, 1942 2,338,140 States Jan. 4, 1944 2,401,529 Varneyet al. June 4, 1946 2,403,691 States July 9, 1946 2,496,237 Smith Jan.31, 1950 2,681,154 Schlumbohm June 15, 1954

1. A PROCESS FOR BREWING COFFEE COMPRISING FORMING GROUND COFFEE IN AMASS, SUBJECTING THE COFFEE TO STREAMS OF WATER AT 185*F. TO 200*F.IMPINGING ON THE CENTER PORTION OF THE MASS AND FILLING THE MASS WITHWATER FORMING A BODY OF HOT WATER WITH A LAYER OF GROUND COFFEE FLOATINGON THE SURFACE OF THE WATER, SUBJECTING THE LAYER OF GROUND COFFEE TOSTREAMS OF HOT WATER I,PINGING ON THE CENTER DOWNWARD AND THENCIRCULATING THE GRANULES OF COFFEE DOWNWARD AND THEN CIRCULATING THEWATER UPWARD TO SWEEP THE WATER ALONG THE BOTTOM OF THE LAYER AND REMOVECOFFEE GRANULES THEREFROM UNTIL A THIN LAYER OF GROUND COFFEE REMAINS ONTHE SURFACE IN BUBBLES OF ESCAPED GASES, DROPPING THE GRANULES DOWNWARDTHROUGH THE WATER TO EXTRACT THE COFFEE THEREFROM WHILE SEPARATING THECOFFEE BREW FROM THE COFFEE GRANULES, SUBJECTING THE REMAINING THINLAYER OF COFFEE TO A DRIPPING ACTION OVER A PERIOD OF TIME TO STRIP THEREMAINING COFFEE GRANULES FROM THE BUBBLES ON THE SURFACE AND FINALLYSEPARATING THE COFFEE BREW FROM THE COFFEE GROUNDS TO FORM A CLEARCOFFEE BREW.